An abstraction and an investigation to the worth of dendritic cells (DCs) ability to collect, process and present antigens are presented. Computationally, this ability is shown to provide a feature reduction mechanism...An abstraction and an investigation to the worth of dendritic cells (DCs) ability to collect, process and present antigens are presented. Computationally, this ability is shown to provide a feature reduction mechanism that could be used to reduce the complexity of a search space, a mechanism for development of highly specialized detector sets as well as a selective mechanism used in directing subsets of detectors to be activated when certain danger signals are present. It is shown that DCs, primed by different danger signals, provide a basis for different anomaly detection pathways. Different antigen-peptides are developed based on different danger signals present, and these peptides are presented to different adaptive layer detectors that correspond to the given danger signal. Experiments are then undertaken that compare current approaches, where a full antigen structure and the whole repertoire of detectors are used, with the proposed approach. Experiment results indicate that such an approach is feasible and can help reduce the complexity of the problem by significant levels. It also improves the efficiency of the system, given that only a subset of detectors are involved during the detection process. Having several different sets of detectors increases the robustness of the resulting system. Detectors developed based on peptides are also highly discriminative, which reduces the false positives rates, making the approach feasible for a real time environment.展开更多
如何合理快速地选取参与导航解算的可见星,是当前北斗/GNSS多系统卫星导航定位亟待解决的关键问题之一。针对此问题,提出一种基于不规则三角网投影的选星算法。该算法的主要思路是,通过一种球内接多面体,投影出Delaunay不规则三角网,快...如何合理快速地选取参与导航解算的可见星,是当前北斗/GNSS多系统卫星导航定位亟待解决的关键问题之一。针对此问题,提出一种基于不规则三角网投影的选星算法。该算法的主要思路是,通过一种球内接多面体,投影出Delaunay不规则三角网,快速计算出球内接多面体体积,得出多面体体积与几何精度因子(geometric dilation of precision,GDOP)的关系,作为选星判断的依据。通过试验计算表明:当参与解算的可见星数量小于11颗时,随着多面体体积的增大,GDOP值减小趋势明显;当可见星数量达到11颗后,GDOP值随着多面体体积增大变化趋势不明显,但解算时效明显降低。据此,在众多可见星中,选择空间几何分布较好的11颗星作为解算卫星,导航定位精度较好,且解算时效也得到兼顾。展开更多
基金Project(50275150) supported by the National Natural Science Foundation of ChinaProjects(20040533035, 20070533131) supported by the National Research Foundation for the Doctoral Program of Higher Education of China
文摘An abstraction and an investigation to the worth of dendritic cells (DCs) ability to collect, process and present antigens are presented. Computationally, this ability is shown to provide a feature reduction mechanism that could be used to reduce the complexity of a search space, a mechanism for development of highly specialized detector sets as well as a selective mechanism used in directing subsets of detectors to be activated when certain danger signals are present. It is shown that DCs, primed by different danger signals, provide a basis for different anomaly detection pathways. Different antigen-peptides are developed based on different danger signals present, and these peptides are presented to different adaptive layer detectors that correspond to the given danger signal. Experiments are then undertaken that compare current approaches, where a full antigen structure and the whole repertoire of detectors are used, with the proposed approach. Experiment results indicate that such an approach is feasible and can help reduce the complexity of the problem by significant levels. It also improves the efficiency of the system, given that only a subset of detectors are involved during the detection process. Having several different sets of detectors increases the robustness of the resulting system. Detectors developed based on peptides are also highly discriminative, which reduces the false positives rates, making the approach feasible for a real time environment.
文摘如何合理快速地选取参与导航解算的可见星,是当前北斗/GNSS多系统卫星导航定位亟待解决的关键问题之一。针对此问题,提出一种基于不规则三角网投影的选星算法。该算法的主要思路是,通过一种球内接多面体,投影出Delaunay不规则三角网,快速计算出球内接多面体体积,得出多面体体积与几何精度因子(geometric dilation of precision,GDOP)的关系,作为选星判断的依据。通过试验计算表明:当参与解算的可见星数量小于11颗时,随着多面体体积的增大,GDOP值减小趋势明显;当可见星数量达到11颗后,GDOP值随着多面体体积增大变化趋势不明显,但解算时效明显降低。据此,在众多可见星中,选择空间几何分布较好的11颗星作为解算卫星,导航定位精度较好,且解算时效也得到兼顾。
